When you hear about immunizations, you probably think of children. In fact, some vaccine-preventable illnesses are more prevalent in adults than children, and many vaccines are recommended for various stages of adult life.

Childhood vaccines can wear off over time, new vaccines become available and older adults who travel afar may want protection against diseases uncommon in the United States. Moreover, as seniors age, a decline in immunity makes them more susceptible to illnesses like shingles, medical experts say.

With the outbreak in measles, the American Medical Association urges adults to get vaccinated against it as the United States battles the most cases since the disease was declared eradicated nearly 20 years ago.

"Adult immunization is important," says Dr. Trish Perl, chief of infectious diseases at UT Southwestern Medical Center in Dallas. "There are a lot of misconceptions. Most vaccines are extremely safe, with no side effects, and they're highly effective."

Vaccines typically contain harmless versions of disease-causing microbes that trick the body's immune system into fighting such germs.

Dr. Gary Goff, a Dallas internist who specializes in adult immunizations, says a simple flu shot "might mean the difference between dying and not dying" for people 50 and older.

(Vernon Bryant/Staff Photographer)

Top three vaccinations

The vaccines that adults need depend on age, lifestyle and health. Doctors and health officials generally recommend three vaccines for people age 50 and older:

Flu: Each year, millions of Americans get the flu, but seniors are more likely to develop complications from it. "Don't miss your annual flu shot," advises Dr. Gary Goff, a Dallas internist who specializes in adult immunizations. "Every year is different because the flu strains change. If you get a flu shot, you can still get the flu, but it might mean the difference between dying and not dying." Records show that nearly 12,000 Texas died from flu or pneumonia during the 2017-18 flu season, with over three-quarters age 65 or older.

Diphtheria, tetanus, pertussis: Seniors should have a shot for diphtheria, tetanus and pertussis -- and get a DTaP booster every 10 years. Especially important for travelers, the vaccine can prevent tetanus bacteria from causing infection in cuts and burns. Adults with pertussis can spread the highly contagious bacteria, which cause violent coughing and difficulty breathing, to infants too young to get vaccinated.

Shingles: Shingles, a painful skin disease that can cause chronic neurological problems, is more common among older adults. The older a person is, the more severe this vaccine-preventable disease is.

For people 65-plus, experts also recommend the pneumococcal vaccine to prevent pneumonia and other infections. Each year, about 900,000 Americans get pneumococcal pneumonia, and 400,000 are hospitalized, according to the Centers for Disease Control and Prevention.

"Travelers tell us where they're going and what they'll do, and we go through the levels of risk," says Arthur Dawson, owner of six Passport Health Dallas Fort-Worth clinics in North Texas. "People going to India and staying in a tourist hotel may not face the same risk as someone who eats at local restaurants."

You can get travel or routine vaccinations from your doctor, a health clinic, pharmacy, county health department or workplace.